What have you tried? Do see that Q & ~Q is a contradiction?
The probability of P = 1/2
The probability of Q = 1/4
Find the probabilities of these statements using truth tables and these rules
Rule 1: If a statement is a tautology (always true), then its probability is 1.
Rule 2: If a statement is a self-contradiction, then its probability is equal to 0.
Rule 3: If two statements are logically equivalent, then they have the same probability.
1. ~(Q&~Q) (Not(Q and not Q)
2.PV(Q&~Q) (P or(Q and not Q)